color filter


Also found in: Dictionary, Wikipedia.

Color filter

An optical element that partially absorbs incident radiation, often called an absorption filter. The absorption is selective with respect to wavelength, or color, limiting the colors that are transmitted by limiting those that are absorbed. Color filters absorb all the colors not transmitted. They are used in photography, optical instruments, and illuminating devices to control the amount and spectral composition of the light.

Color filters are made of glass for maximum permanence, of liquid solutions in cells with transparent faces for flexibility of control, and of dyed gelatin or plastic (usually cellulose acetate) for economy, convenience, and flexibility. The plastic filters are often of satisfactory permanence, but they are sometimes cemented between glass plates for greater toughness and scratch resistance. They do not have as good quality as gelatin filters.

Color filters are sometimes classified according to their type of spectral absorption: short-wavelength pass, long-wavelength pass or band-pass; diffuse or sharp-cutting; monochromatic or conversion. The short-wavelength pass transmits all wavelengths up to the specified one and then absorbs. The long-wavelength pass is the opposite. Every filter is a band-pass filter when considered generally. Even an ordinary piece of glass does not transmit in the ultraviolet or infrared parts of the spectrum. Color filters, however, are usually discussed in terms of the portion of the visible part of the spectrum. Sharp and diffuse denote the sharpness of the edges of the filter band pass. Monochromatic filters are very narrow band-pass filters. Conversion filters alter the spectral response or distribution of one selective detector or source to that of another, for example, from that of a light bulb to that of the Sun. See Absorption of electromagnetic radiation, Color

color filter

[′kəl·ər ‚fil·tər]
(optics)
An optical element that partially absorbs incident light, consisting of a pane of glass or other partially transparent material, or of films separated by narrow layers; the absorption may be either selective or nonselective with respect to wavelength. Also known as light filter.
References in periodicals archive ?
The chromaticity coordinates can be estimated by measuring the degree of depolarization of the polarizer and the color filter. The error of chromaticity can be analyzed by introducing three backlight units and color resists.
That's why we made our second rear camera a true monochrome camera, which does not require any color filter. The lack of a color filter means that no interpretation is necessary-every pixel is assigned a true black or white value, which enables the camera to produce images with much less noise and much higher resolution, no matter the lighting conditions.
The schematic of this modified etalon color filter is shown in Figure 7(a) and the simulated transmission spectra are shown in Figure 7(b).
Image information is obtained after passing through a Bayer pattern color filter array.
Among the key component segment, production value of color filter, polarizer, grass substrate, and backlight module reached NT$27.2 billion (US$906.67 million), NT$23.51 billion (US$783.67 million), NT$37.39 billion (US$1.25 billion), and NT$40.09 billion (US$1.34 billion), respectively.
The Color Filter function is completely automatic, and colors can be easily extracted while watching the monitor.
hazing into a blue color filter, a painted alley wall.
They describe CCD and CMOS fundamentals; introduce array parameter issues such as well capacity, dark pixels, microlenses, and color filter arrays; explore the topics of quantum efficiency, responsivity, and noise sources; examine signal-to-noise ratio in terms of both radiometric units for scientific applications and photometric units for consumer applications; discuss image quality and its links to the system modulation transfer function and linear system theory; and describe different mathematical approaches to image quality.
Coupled with a built-in Bayer color filter, Peltier cooling, and advanced multi-functional software, this camera contains all the features necessary to maximize and streamline workflow.
Toray said it will supply color filter products to Samsung Electronics Co.
NEC's Capsulated Color Filter technology offers realistic color reproduction and its AccuCrimson technology creates the purest reds possible in a plasma display, while its MASS technology eliminates jagged lines and corrects color bleeds for clear and defined images.